US6676380B2 - Turbine blade assembly with pin dampers - Google Patents
Turbine blade assembly with pin dampers Download PDFInfo
- Publication number
- US6676380B2 US6676380B2 US10/120,584 US12058402A US6676380B2 US 6676380 B2 US6676380 B2 US 6676380B2 US 12058402 A US12058402 A US 12058402A US 6676380 B2 US6676380 B2 US 6676380B2
- Authority
- US
- United States
- Prior art keywords
- turbine blade
- pins
- turbine
- blade assembly
- damper cavity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/26—Antivibration means not restricted to blade form or construction or to blade-to-blade connections or to the use of particular materials
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S416/00—Fluid reaction surfaces, i.e. impellers
- Y10S416/50—Vibration damping features
Definitions
- the present invention relates to turbines and, more particularly, to the vibration damping of turbine blades thereof.
- Turbines are commonly used to provide power to pump fluids, move vehicles, or generate electricity.
- the main power-producing component of a turbine is the turbine blade.
- Turbine blades are aerodynamically shaped vanes connected to the perimeter of a disk that rotates on a shaft. The blades are shaped so that, when a driving fluid passes over the surface, a force is generated causing the disk to rotate. They are usually manufactured as separate components that are subsequently attached to the disk by various means. Recently, however, turbine blades have been machined as integral parts of the disk. This one-piece integral blade/disk design is commonly referred to as a blisk.
- turbine blades are subjected to alternating fluid forces that can cause high cycle fatigue failure, particularly if the frequency of the alternating force coincides with one of the natural vibration frequencies of the blade.
- vibration dampers have been used to reduce the magnitude of the dynamic stresses, thereby increasing operational life.
- Most turbine blade vibration dampers consist of small metallic pieces that form a connection between two adjacent blades. Blade vibration causes motion at the blade/damper interfaces resulting in energy dissipation by friction. Since blisks consist of a single piece with no joints to dissipate vibration energy, they are particularly sensitive to operation near the natural frequencies of the blade/disk system. Turbine blades are designed to avoid primary resonant points but it is impossible to prevent this operation at all of the many blade natural frequencies. Therefore, additional damping must be provided to reduce resonant response of the blade/disk system.
- U.S. Pat. No. 5,232,344 issued to Y. M. El-Aini, discloses a twisted hollow fan or compressor airfoil blade that extends radially from the rotor shaft. It has a plurality of internal chambers, each one bounded by the blade skin on two sides. A slug is located within at least one of these chambers, with the slug under the influence of centrifugal force in contact with the outboard section and also with one of the skins. It is in contact with the skins at two transversely spaced locations so that friction occurs between the two components.
- U.S. Pat. No. 5,498,137 issued to Y. M. El-Aini et al., discloses a rotor blade for a turbine engine rotor assembly comprising a root, an airfoil, a platform, and apparatus for damping vibrations in the airfoil.
- the airfoil includes a pocket formed in a chordwise surface.
- the apparatus for damping vibrations in the blade includes a damper and a pocket lid. The damper is received within the pocket between an inner surface of the pocket and the pocket lid.
- the pocket lid is attached to the airfoil by conventional attachment apparatus and contoured to match the curvature of the airfoil.
- U.S. Pat. No. 5,820,343, issued to R. J. Kraft et al. discloses a rotor blade for a rotor assembly that includes a root, an airfoil, a platform, and a damper.
- the airfoil includes at least one cavity.
- the platform extends laterally outward from the blade between the root and the airfoil, and includes an airfoil side, a root side, and an aperture extending between the root side of the platform and the cavity within the airfoil.
- the damper which includes at least one bearing surface, is received within the aperture and the cavity. The bearing surface is in contact with a surface within the cavity and friction between the bearing surface and the surface within the cavity reduces vibration of the blade.
- U.S. Pat. No. 5,165,860 issued to A. W. Stoner et al., discloses a turbine blade with an internal damper that comprises an elongated member with a damping surface of discrete width in contact with an interior surface of the blade. This contact is continuous throughout a contact length greater than 50% of the effective radial length. The contact is in the direction having a radial component with respect to the axis of the rotor, preferably with the damper extending between 2 degrees and 30 degrees from the radial direction. This damping surface is the exclusive frictional contact between the damper and the blade.
- U.S. Pat. No. 5,407,321 issued to D. A. Rimkunas et al., discloses the use of an elongated spring-like damper element that is shaped in the cross section of a “V” or “U” and inserted through a hole formed on one end of the ends of an airfoil of a stator vane.
- the legs of the “V” or “U” shaped element are adapted to bear against the inner surface of the airfoil and provide damping through frictional loss during vibration.
- U.S. Pat. No. 6,283,707 discloses a damper for an airfoil blade that comprises an elongated member that is inserted within a core passage in the blade.
- the damper is retained in the blade at the end closest to the blade root with the remainder of the damper free to move relative to and within the passage.
- the damper comprises a resilient plate insert upon which there are provided at least two discrete, oppositely directed, contact regions which are arranged to frictionally engage the passage.
- the present invention is a turbine blade assembly for a turbine assembly.
- the turbine blade assembly includes a turbine blade having a turbine blade damper cavity formed therein.
- a plurality of pins are positioned within the turbine blade damper cavity and are maintained there during operation of the turbine blade assembly. The pins reduce vibration of the turbine blade assembly during operation by dissipating energy through friction between the adjacent pins and between the pins and internal surface of the blade that defines the damper cavity.
- This invention minimizes turbine blade high cycle fatigue failures by adding damping to reduce dynamic stresses. Damping is obtained through energy dissipation by friction in the internally mounted bundle of small pins.
- the pins are held in place by a cap on the outer portion of the hole. During blade vibration, the pins move relative to each other and have been shown to reduce vibration stresses by as much as a factor of 25.
- FIG. 1 is an end view of a preferred embodiment of the turbine blade assembly of the present invention.
- FIG. 3 is an end view of another embodiment of the turbine blade assembly of the present invention.
- FIG. 4 is a cross-sectional view of the embodiment of FIG. 3, shown along Line 4 — 4 of FIG. 3 .
- FIGS. 1 and 2 illustrate a preferred embodiment of the turbine blade assembly of the present invention, designated generally as 10 .
- the turbine blade assembly 10 includes a turbine disk 12 that supports a turbine blade 14 .
- the turbine blade 14 has an internal surface 16 defining a turbine blade damper cavity.
- the turbine blade damper cavity 16 extends from an opening in the distal end, i.e. tip 18 , of the turbine blade 14 opposite the turbine disk 12 .
- Damper cavity 16 may, for example, be cylindrical and extend into the turbine blade 14 substantially parallel to or along a longitudinal axis 20 of the turbine blade 14 .
- the turbine blade longitudinal axis 20 extends substantially radially outward, i.e.
- the turbine blade longitudinal axis 20 extends in a range of about 0°-10° from the radially outward direction from the central axis.
- the turbine blade damper cavity 16 extends in a range of about 0°-45° from the turbine blade longitudinal axis 20 .
- Pins 22 are positioned within the turbine blade damper cavity 16 .
- the pins may have circular cross-sections but are not restricted to be of circular cross-section. They can be square, hexagonal or any other suitable shape that dissipates energy by friction within the pin bundle as well as between the walls of the cavity 16 and the outer pins in the pin bundle.
- the pins 22 may be formed of any metallic or non-metallic material. They generally have diameters in a range of about 0.010-0.050 inches, preferably about 0.020 inches. They are preferably fitted within the cavity 16 sufficiently to provide a snug fit.
- the shape of the turbine blade damper cavity 16 and number of pins 22 is dictated by the turbine blade geometry.
- the turbine blade damper cavity 16 is capped after installation of the pins 22 by a damper cavity cap 24 that is firmly held into position by either screw threads, welding, or any other suitable means.
- FIGS. 1-2 involves machining a central cavity 16 radially inward from the distal end 18 .
- more than one cavity can be used.
- the single or multiple cavities can be machined radially outwardly from the bottom of the turbine disk.
- FIGS. 3 and 4 an alternate embodiment is illustrated, designated generally as 30 .
- three turbine blade damper cavities 32 , 34 , 36 are machined radially outward from the underside of the turbine disk 38 through the proximal end of the turbine blade 40 .
- the use of a relatively large central cavity 32 and two smaller cavities 34 , 36 allows maximal utilization of the volume of the turbine blade 40 .
- a primary advantage of the present invention is that the damper pins are completely contained within the turbine blade. There are no connections between blades that require external features to support the pins. Most present turbine blade dampers must span from blade to blade in order to use the relative motion between blades for damping. This generally restricts them to blade configurations that are mechanically attached to the disk because assembling a damper between blades requires the blades to be removable. External mounting configurations also leave the dampers exposed to the high velocity gas flow, which can lead to failure of the damper.
- This invention allows the damper elements, i.e. pins, to be placed within the turbine blade itself. These damper pins can be easily used on turbines with integral blades because installation of the damper cavity and pins do not require removal of the blade from the disk.
- This invention can also be retrofitted to existing undamped turbine blisks.
- Major modification to the hardware is not required since additional material is not added to the blade to accommodate the damper cavity and pins.
- the retrofit only requires removing material from the blade.
- the modification involves making the cavity in the blade, installing the damping pins, and closing the cavity. Lead-time to get back into testing is reduced since existing hardware can be modified as opposed to waiting for a new production run of blades.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
Description
Claims (94)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/120,584 US6676380B2 (en) | 2002-04-11 | 2002-04-11 | Turbine blade assembly with pin dampers |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/120,584 US6676380B2 (en) | 2002-04-11 | 2002-04-11 | Turbine blade assembly with pin dampers |
Publications (2)
Publication Number | Publication Date |
---|---|
US20030194324A1 US20030194324A1 (en) | 2003-10-16 |
US6676380B2 true US6676380B2 (en) | 2004-01-13 |
Family
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Application Number | Title | Priority Date | Filing Date |
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US10/120,584 Expired - Lifetime US6676380B2 (en) | 2002-04-11 | 2002-04-11 | Turbine blade assembly with pin dampers |
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US (1) | US6676380B2 (en) |
Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070081894A1 (en) * | 2005-10-06 | 2007-04-12 | Siemens Power Generation, Inc. | Turbine blade with vibration damper |
US20070253828A1 (en) * | 2003-12-02 | 2007-11-01 | Pierre-Alain Masserey | Damping arrangement for a blade of an axial turbine |
US7806410B2 (en) | 2007-02-20 | 2010-10-05 | United Technologies Corporation | Damping device for a stationary labyrinth seal |
US8262363B2 (en) | 2008-03-17 | 2012-09-11 | General Electric Company | Blade having a damping element and method of fabricating same |
US9151170B2 (en) | 2011-06-28 | 2015-10-06 | United Technologies Corporation | Damper for an integrally bladed rotor |
US20170321557A1 (en) * | 2016-05-09 | 2017-11-09 | MTU Aero Engines AG | Impulse element module for a turbomachine |
US11085303B1 (en) | 2020-06-16 | 2021-08-10 | General Electric Company | Pressurized damping fluid injection for damping turbine blade vibration |
US11143036B1 (en) | 2020-08-20 | 2021-10-12 | General Electric Company | Turbine blade with friction and impact vibration damping elements |
US11242756B2 (en) | 2020-05-04 | 2022-02-08 | General Electric Company | Damping coating with a constraint layer |
US11365636B2 (en) | 2020-05-25 | 2022-06-21 | General Electric Company | Fan blade with intrinsic damping characteristics |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US12371999B2 (en) | 2023-12-29 | 2025-07-29 | Rtx Corporation | Damping system for an integrally bladed rotor |
Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2349187A (en) * | 1941-03-08 | 1944-05-16 | Westinghouse Electric & Mfg Co | Vibration dampener |
US2809802A (en) * | 1952-09-10 | 1957-10-15 | Gen Electric | Damping turbine blades |
US2930581A (en) * | 1953-12-30 | 1960-03-29 | Gen Electric | Damping turbine buckets |
US2999669A (en) * | 1958-11-21 | 1961-09-12 | Westinghouse Electric Corp | Damping apparatus |
US4484859A (en) | 1980-01-17 | 1984-11-27 | Rolls-Royce Limited | Rotor blade for a gas turbine engine |
US5165860A (en) | 1991-05-20 | 1992-11-24 | United Technologies Corporation | Damped airfoil blade |
US5232344A (en) | 1992-01-17 | 1993-08-03 | United Technologies Corporation | Internally damped blades |
US5407321A (en) | 1993-11-29 | 1995-04-18 | United Technologies Corporation | Damping means for hollow stator vane airfoils |
US5498137A (en) | 1995-02-17 | 1996-03-12 | United Technologies Corporation | Turbine engine rotor blade vibration damping device |
US5820343A (en) | 1995-07-31 | 1998-10-13 | United Technologies Corporation | Airfoil vibration damping device |
US6155789A (en) * | 1999-04-06 | 2000-12-05 | General Electric Company | Gas turbine engine airfoil damper and method for production |
US6283707B1 (en) | 1999-03-19 | 2001-09-04 | Rolls-Royce Plc | Aerofoil blade damper |
-
2002
- 2002-04-11 US US10/120,584 patent/US6676380B2/en not_active Expired - Lifetime
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2349187A (en) * | 1941-03-08 | 1944-05-16 | Westinghouse Electric & Mfg Co | Vibration dampener |
US2809802A (en) * | 1952-09-10 | 1957-10-15 | Gen Electric | Damping turbine blades |
US2930581A (en) * | 1953-12-30 | 1960-03-29 | Gen Electric | Damping turbine buckets |
US2999669A (en) * | 1958-11-21 | 1961-09-12 | Westinghouse Electric Corp | Damping apparatus |
US4484859A (en) | 1980-01-17 | 1984-11-27 | Rolls-Royce Limited | Rotor blade for a gas turbine engine |
US5165860A (en) | 1991-05-20 | 1992-11-24 | United Technologies Corporation | Damped airfoil blade |
US5232344A (en) | 1992-01-17 | 1993-08-03 | United Technologies Corporation | Internally damped blades |
US5407321A (en) | 1993-11-29 | 1995-04-18 | United Technologies Corporation | Damping means for hollow stator vane airfoils |
US5498137A (en) | 1995-02-17 | 1996-03-12 | United Technologies Corporation | Turbine engine rotor blade vibration damping device |
US5820343A (en) | 1995-07-31 | 1998-10-13 | United Technologies Corporation | Airfoil vibration damping device |
US6283707B1 (en) | 1999-03-19 | 2001-09-04 | Rolls-Royce Plc | Aerofoil blade damper |
US6155789A (en) * | 1999-04-06 | 2000-12-05 | General Electric Company | Gas turbine engine airfoil damper and method for production |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070253828A1 (en) * | 2003-12-02 | 2007-11-01 | Pierre-Alain Masserey | Damping arrangement for a blade of an axial turbine |
US7300256B2 (en) * | 2003-12-02 | 2007-11-27 | Alstom Technology Ltd. | Damping arrangement for a blade of an axial turbine |
US20070081894A1 (en) * | 2005-10-06 | 2007-04-12 | Siemens Power Generation, Inc. | Turbine blade with vibration damper |
US7270517B2 (en) | 2005-10-06 | 2007-09-18 | Siemens Power Generation, Inc. | Turbine blade with vibration damper |
US7806410B2 (en) | 2007-02-20 | 2010-10-05 | United Technologies Corporation | Damping device for a stationary labyrinth seal |
US8262363B2 (en) | 2008-03-17 | 2012-09-11 | General Electric Company | Blade having a damping element and method of fabricating same |
US10087763B2 (en) | 2011-06-28 | 2018-10-02 | United Technologies Corporation | Damper for an integrally bladed rotor |
US9151170B2 (en) | 2011-06-28 | 2015-10-06 | United Technologies Corporation | Damper for an integrally bladed rotor |
US20170321557A1 (en) * | 2016-05-09 | 2017-11-09 | MTU Aero Engines AG | Impulse element module for a turbomachine |
US10570752B2 (en) * | 2016-05-09 | 2020-02-25 | MTU Aero Engines AG | Impulse element module for a turbomachine |
US11242756B2 (en) | 2020-05-04 | 2022-02-08 | General Electric Company | Damping coating with a constraint layer |
US11365636B2 (en) | 2020-05-25 | 2022-06-21 | General Electric Company | Fan blade with intrinsic damping characteristics |
US11702940B2 (en) | 2020-05-25 | 2023-07-18 | General Electric Company | Fan blade with intrinsic damping characteristics |
US12110805B2 (en) | 2020-05-25 | 2024-10-08 | General Electric Company | Fan blade with intrinsic damping characteristics |
US11085303B1 (en) | 2020-06-16 | 2021-08-10 | General Electric Company | Pressurized damping fluid injection for damping turbine blade vibration |
US11143036B1 (en) | 2020-08-20 | 2021-10-12 | General Electric Company | Turbine blade with friction and impact vibration damping elements |
Also Published As
Publication number | Publication date |
---|---|
US20030194324A1 (en) | 2003-10-16 |
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